Hydrofoil watercraft



Oct. 11, 1960 D. R. PALMER ETAL 2,955,559

HYDROFOIL WATERCRAFT 3 Sheets-Sheet 1 Filed April 4, 1957 Fig./

Donald R. Palmer Robert H. Olson INVENTORS,

BY M5510 3% Fig.3

Oct. 11, 1960 D. R. PALMER ETAL 2,955,559

HYDROF'OIL WATERCRAFT 3 Sheets-Sheet 2 Filed April 4, 1957 EA III I Donald R. Palmer Robert H. Olson INVENTORSI,

Amrnq:

Oct. 11, 1960 D. R. PALMER ETAL 2,955,559

HYDROFOIL WATERCRAFT Filed April 4, 1957 Fig.7

5 Sheets-Sheet 3 Fig.9

Donald R. Palmer Rob er/ H. Olson IN VEN TORS Unite States Patent 2,955,559 Patented Oct. 11, 1960 HYDROFOIL WATERCRAFT Filed Apr. 4, 1957, Ser. No. 650,628

Claims. (Cl. 11466.5)

This invention relates in general to new and useful improvements in marine craft and more specifically to an improved marine craft of the hydrofoil type.

In the past it has been well known that by placing hydrofoils beneath a hull and propelling the hull at a sufficient speed for the hydrofoil to have suflicient lift to support the entire marine craft, the hull of the marine craft will lift from the water and the craft will continue through the water at a higher rate of speed supported only by the hydrofoil. However, marine craft of the hydrofoil type heretobefore have been relatively bulky and expensive to manufacture so as to be limited to craft of experimental types. It is therefore the primary object of this invention to provide a marine craft of the hydrofoil type which is of extremely simple construction and is of such a nature whereby it is relatively inexpensive so as to be usable for pleasure purposes.

Another object of this invention is to provide an improved marine craft of the hydrofoil type, the craft including a simple lightweight hull carrying an inexpensive comparatively low power propulsion unit, the hull being intended to seat a single operator and being provided with a simple control mechanism of the handle bar type whereby a forward supporting foil may be controlled for both lifting the hull out of the water and for steering the hull when lifted from the water.

Another object of this invention is to provide an improved watercraft of the hydrofoil type, the watercraft including a high speed lightweight hull having an outboard motor mounted on the stern thereof and being equipped with an aft supporting foil with respect to a forward supporting foil which is mounted for steering and which is mounted to have the angle of incident thereof varied to effect the raising and lowering of the hull from the water, the marine craft being provided with a simple control of a handle bar type for steering and changing the angle of incident of the forward supporting foil.

A further object of this invention is to provide an im: proved marine craft of the hydrofoil type, the marine craft including a hull having a propulsion unit, there being mounted at the stern of the hull a fixed horizontally,

disposed aft supporting foil and there being carried by a forward portion of the hull a forward supporting foil which is mounted for pivotal movement about a horizontal axis in order to change the angle of incident thereof and which is provided with positive dihedral.

These together with other objects and advantages which will become subsequently apparent reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forminga part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a plan view of the marine craft and shows the general arrangement of the steering control means;

Figure 2 is a side elevational view of the marine craft of Figure 1 and shows the relationship of the supporting foil and the outboard motor;

Figure 3 is a bottom plan view of the marine'craft of Figure 1;

Figure 4 is an enlarged fragmentary sectional view taken substantially upon the plane indicated by the section line 44 of Figure 1 and shows the specific details of the control for the forward supporting foil in a manner in which it is mounted;

Figure 5 is an enlarged fragmentary bottom plan view showing further the details of mounting of the forward supporting foil;

Figure 6 isv an enlarged fragmentary horizontal sectional view taken substantially upon the plane indicated by the section line 66 of Figure 4;

Figure 7 is a front elevational view of the marine craft of Figure 1;

Figure 8 is a rear elevational view of the marine craft of Figure 1;

Figure 9 is a rear elevational view of a modified form of aft supporting foil, the outboard motor being shown in phantom lines and the forward supporting foil being omitted for purposes of clarity; and

Figure 10 is an enlarged fragmentary sectional view taken substantially upon the plane indicated by section line Ill-10 of Figure 9 and shows the manner in which the aft supporting foil is secured to the transom of the hull.

Referring now to the drawings in detail, it will be seen that the marine craft is referred to by the reference numeral 10. The marine craft 10 includes a hull 12 of a suitable design. It is preferred that the hull 12 be of the sea-sled type and that it be extremely light. However, any small high speed hull which'is ofa lightweight may suflice.

. foil '50 is notched as at 52 to provide clearance for the The hull 12 includes a bottom 14 and a deck 16 which} are connected together by suitable supporting ribs 18.-

The hull'12 also includes a transom 20 having an upwardly projecting central portion 22. central portion 22 is an outboard motor 24 having a motor shaft housing 26 which is of an extra length. At the lower end of the motor shaft housing 26 is a propeller 28. I In order that the marine craft 10 may operate through the water with the hull 12 disposed above the surface of the water, there is secured to the outboard motor 24 above the propeller '28 an aft supporting foil 30. The aft supporting foil 36 is horizontally disposed and is preferably secured to a cavitation plate 32 which extends to opposite sides of the motor shaft housing 26 as is shown in Figure 8. i

Referring now to Figure 4 in particular, it will be seen that there is mounted in the forward portion of the hull 12 between the bottom 14 and the deck 16a bearing assembly 34 of the thrust type. Journaled in the bearing assembly 34 for rotation about a generally vertical axis is a sleeve 36. The sleeve 36 extends both upwardly tween the sleeve 36 and the bottom .14.

The sleeve '36 terminates at its lower end a mounting plate 40 to which there is secured an upper flange 42 of a tubular strut '44. The strut 44 is of the streamline type and is provided at its lower end with a pair of forwardly projecting cars 46 which are transversely spaced, as

shown in Figure 5. Extending between the ears 46 is a; shaft 48 on which there is mounted for pivotal movement a forward supporting foil 50. The forward supporting forward part of the strut 44.

Telescoped within the upper part of the sleeve 36 andextending upwardly therefrom is a tubular steering col-' umn 54. The steering column is retained in anadjusted. position with respect to the sleeve 36.by means of it Mounted on the setscrew 56. Incidentally, the sleeve 36 is retained within the bearing 34 by means of a collar 58 mounted on the upper part thereof and secured in place by a setscrew 60. 'The collar 58 bears on the deck 16 or a suitable bearing plate (not shown).

The steering column 54 is provided at the upper end thereof with a mounting collar 62 which has extending therethrough an intermediate portion 64 of a handle bar type control 66. Thus the handle bar type control 66 is mounted for pivotal movement about a horizontal axis.

Secured to the intermediate portion 64 of the handle bar type control 66 is a vertical leg 68 of a crank-type lever 70. The crank-type lever 70 also includes a horizontal leg 72 which overlies the upper end of the steering column 54. Extending downwardly through the steering column 54, the sleeve 36 and the hollow strut 44 is a control link 74. The upper end of the control link 74 is disposed in an elongated slot 76 in the horizontal leg of the crank-type lever 70.

Secured to the underside of the forward supporting foil 50 is a depending flange 77 which has rigidly secured thereto an operating arm 78. Pivotally connected to the operating arm78 as at 80 is the lower end of the control link 74. Thus by moving the handle bar type control 66 upwardly, the positive angle of incident will be assumed by the forward supporting foil 50. On the other hand, should the handle bar type control 66 be moved downwardly, a negative angle of incidence will be assumed by the forward supporting foil 50.

As is best shown in Figure 7, the forward supporting foil 50 has a positive dihedral. Inasmuch as the handle bar type control 66 is rigidly secured to the steering column 54 other than its mounting for movement about a. horizontal axis, it will be readily apparent that the strut 44 and the forward supporting foil 50 may be turned as desired. Because of the positive dihedral of the forward supporting foil 50, when the forward supporting foil 50 is turned, it will function to control the direction of movement of the hull 12.

Extending between the outboard motor 24 and the handle bar type control 66 is a control cable 82 for the outboard motor 24. Thus, the outboard motor 24 may be regulated by the operator of the marine craft from a remote point. In order that the operator may be comfortably seated, there is provided a seat 84 rearwardly of the handle bar type control 66.

As in the case of other marine craft of the hydrofoil type, when sufficient speed has been attained by the hull 12, the angle of incidence of the forward supporting foil 50 may be changed so as to effect lift thereby. When this happens, the lifting surfaces of the forward supporting foil 50 and the aft supporting foil will be sufficient to cause elevation of the hull 12 above the water and the supporting of the marine craft 10 entirely on the supporting foils 30 and 50. When operating in this condition, there is less resistance to movement of the marine craft 10 through the water and as a result greater speed may be obtained.

Referring now to Figures 9 and 10 in particular, it will be seen that there is illustrated a modified form of marine craft which is referred to by the reference numeral 90. The marine craft 90 includes a hull 92 which is of identical construction with the hull 12 with the exception that the hull 92 includes a transom 94 with a relatively wide upwardly projecting portion 96 as compared to the narrower upwardly projecting portion 22 of the transom 20. Secure to the central part of the upwardly projecting portion 96 will be an outboard motor 98 which will be identical to the outboard motor 24 with the exception that the aft supporting foil 30 is omitted.

Secured to the transom 94 on opposite sides of the position which will normally be maintained by the outboard motor 98 are mounting brackets 100 which include mountingplates 102 secured to the transom 94 by fasteners 104.

Extending rearwardly from each of the mounting plates.

' a lower pin 116 which rest upon the lower ears 106.

The lower pin 116 is retained in place by a spring-loaded catch 113. Extending rearwardly through the transom 94 and the mounting plate 102 is a threaded fastener 120 which also passes through the upper part of the strut 112 to secure the strut 112 in place.

As is best shown in Figure 9, the struts 112 are vertically disposed and are in spaced relation on opposite sides of the outboard motor 98. Extending between the lower ends of the struts 112 and supported thereby is an aft supporting foil 122. The aft supporting foil 122 is horizontally disposed and will be similar to the aft supporting foil 30.

From the foregoing description of the present invention it will be seen that there has been devised a marine craft which is of the hydrofoil type and which is of extremely simple construction so as to be economically feasible. Further, the hydrofoil assembly of the marine craft is such that it is effective in operation and at the same time may be easily controlled for the effective controlling of the marine craft by means of a simple control mechanism.

The foregoing is considered as illustrative only of the principles of the invention. Further, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction and operation shown and described, and accordingly all suitable modifications and equivalents may be resorted to, falling within the scope of the invention as claimed.

What is claimed as new is as follows:

1. A marine craft of the hydrofoil type comprising a hull including a stern, a propulsion unit mounted on said hull, said propulsion unit including a propulsion device of the water reaction type disposed at said stern and in spaced relation below said hull, a fixed aft supporting foil, means carried by said hull supporting said aft supporting foil below the plane of said hull and adjacent said propulsion device, a support depending below a forward part of said hull, means on said hull mounting said support for rotation about its axis, a forward supporting foil, means carried by said support mounting said forward supporting foil on said support for pivotal movement about a horizontal axis to change the angle of incidence, said forward supporting foil having positive dihedral to effect the steering of the craft, said support extending through and above said hull, a handle bar type of control secured to said support above said hull for effecting rotation thereof, means pivotally connecting said handle bar type control to said support for swinging movement about a horizontal axis, linkage extending between said handle bar type control and said forward supporting foil for changing the angle of incidence ofsaid forward foil by vertically swinging said handle bar type control.

2. The marine craft of claim 1 wherein said support is tubular and a portion of said linkage extends through said support.

3. A marine craft of the hydrofoil type, a light weight high speed hull including a stern, an outboard motor secured to said stern, said outboard motor having a portion thereof extending below said hull and including a propeller disposed below the plane of the bottom of said hull, a fixed aft supporting foil rigidly mounted on said outboard motor adjacent said propeller and below the plane of said hull, a forward supporting foil, a support depending below a forward part of said hull, means on said hull mounting said support for rotation about its axis, means carried by said support mounting said forward supporting foil on said support for pivotal movement about a horizontal axis to change the angle of incidence thereof, said forward supporting foil having positive dihedral to effect the steering of the craft, said support extending through and above said hull, a handle bar type of control secured to said support above said hull for efiecting rotation thereof, means pivotally connecting said handle bar type control to said support for swinging movement at a horizontal axis, linkage extending between said handle bar type control and said forward supporting foil fior changing the angle of incidence of said forward supporting foil by vertically swinging said handle bar type con-- trol.

4. The marine craft of claim 3 wherein said support is tubular and a portion of said linkage extends through said support.

5. The combination of claim 4 wherein said forward supporting foil is disposed forwardly on said support, said support having a streamlined and elongated horizontal cross-section extending longitudinally of said craft when said support is positioned to steer the craft in a straight line.

References Cited in the file of this patent UNITED STATES PATENTS 1,186,816 Meacham et al June 13, 1916 1,515,649 Baldwin Nov. 18, 1924 1,835,618 Waller Dec. 8, 1931 2,081,868 Hampden May 25, 1937 2,274,200 Hill Feb. 24, 1942 2,584,347 Hazard Feb. 5, 1952 2,748,400 Kregall June 5, 1956 2,795,202 H'ook June 11, 1957 OTHER REFERENCES The Rudder, July 1956, pages 14-15. 

